EV Charger fed by 240/3 delta panel

[Npstewart]

Hello everyone.

Im curious if anyone would have any hesitation feeding an EV car charger using the high leg of a 240/3 delta panel.

I have a condo building with an existing 240/3 panel. The panel is full except for all the remaining high-leg spaces but they are looking to add (2) single phase chargers which would either require a new panel, or require those high-leg spaces to be used. I would expect the EV chargers to be fine, especially because all of the ones ive seen do not require a neutral conductor but there are quite a few EV chargers out there and some may operate differently than others, or perhaps some check the L-G voltage indivudally.

Thank you in advance for the input

 

[LarryFine]

A L-L load that doesn't reference (use) the neutral may be supplied by the high leg and either other line.

I would place them with one between line A and the high leg, and the other between C and the high leg.

 

[curt swartz]

I can't tell you how the chargers will react to being fed by a grounded conductor and one conductor 208 volts to ground.

I don't know what panel you have but it its a standard 120/240 volt rated panel they don't make single pole breakers rated to straight 240 volts.

Typically when residential buildings are fed with the delta service there is only a small 3 phase load such as an elevator. The utility will install a large transformer for the 120/240 single phase loads and a small transformer just large enough to supply the 3 phase load. Adding a large load is not a good idea.

 

[tortuga]

If the nameplate says '240' or '230' and not 120/240 it should work on 240V L-N type systems like they have in most other countries.
Seems like a great use of some extra hi-leg spots (B phase). You of course would need a 'straight rated' 240V 2-pole breaker and a A or C phase spot also.

 

[LarryFine]

I can't tell you how the chargers will react to being fed by a grounded conductor and one conductor 208 volts to ground.

I obviously took it to mean line-to-line, not line-to-neutral. It's never good to use the latter on a high-leg.

 

[curt swartz]

I obviously took it to mean line-to-line, not line-to-neutral. It's never good to use the latter on a high-leg.

We will need the OP to reply but they said the only open spaces were the high leg so I assumed the high leg and grounded conductor.

 

[Npstewart]

I was planning on a 60A/2P circuit breaker to provide 240v single phase. Theres 2 single pole spaces left so the breakers would have to be re-arranged to get 2 spaces adjacent to eachother.

 

[tortuga]

I was planning on a 60A/2P circuit breaker to provide 240v single phase. Theres 2 single pole spaces left so the breakers would have to be re-arranged to get 2 spaces adjacent to eachother.

just be sure to use a straight '240' rated breaker and your good to go

 

[winnie]

If you only have B spaces available, then you _can't_ rearrange the breakers to open adjacent spaces without finding some other load to move to a B space.

Any straight 240V L-L loads can have one leg on the B phase.

Any 120/240V L-N-L loads will likely have a problem with the B phase. This may include loads which don't use N as a power lead but do use ground as a signal reference.

-Jonathan

 

[jim dungar]

It used to not be a big deal, but times are changing.
When using the high leg be careful of electronic components that may have filters connected line-ground, such as VFDs.

 

[electrofelon]

I connect all sorts of L-L stuff including "sensitive electronics" to the high leg and have never had an issue.

 

[Charged]

I’ve seen a lot of manufacturers have problems and indicate the grounding of the 240 that will give not work with the chargers. Ie corner grounded system vs center grounded system. I can’t think of the exact problem but I would review the installation manual.

 

[kwired]

I connect all sorts of L-L stuff including "sensitive electronics" to the high leg and have never had an issue.

If they have a surge protector with line to line, line to ground and other line line to ground protection chances are you burn out the side of it connected to high leg to ground but won't have any other issues - until non filtered surges on that damaged portion get to the sensitive items.

 

[Jpflex]

A L-L load that doesn't reference (use) the neutral may be supplied by the high leg and either other line.

I would place them with one between line A and the high leg, and the other between C and the high leg.

But will the line to “stinger” give him the proper voltage?

 

[LarryFine]

But will the line to “stinger” give him the proper voltage?

Yes. A delta is an equilateral triangle. Regardless of each L-N voltage, the L-L voltages are equal.

 

[LarryFine]

I just found a great picture of both delta and wye transformer banks. The wye system in the background has all three units' neutrals tied together, and the three 120v outputs form the three lines.

In the nearer bank, the center transformer is (wired exactly like) a 1ph 120/240v unit, because that's exactly what it is. It provides 120v and 240v via the A and C phase lines and the neutral.

The other two transformers put out 240v only (center taps float), and complete the triangle. Here, they happen to meet at the bottom insulator on the pole and form the B phase's line.

Added: It's possible that the wye system is 480Y/277. I looked closer and noticed that the transformers each have only two secondary bushings.